TEHRAN, May 23 -- Iran has followed President Mahmoud Ahmadinejad's recent letter to President Bush with explicit requests for direct talks on its nuclear program, according to U.S. officials, Iranian analysts and foreign diplomats.

The eagerness for talks demonstrates a profound change in Iran's political orthodoxy, emphatically erasing a taboo against contact with Washington that has both defined and confined Tehran's public foreign policy for more than a quarter-century, they said.

Though the Tehran government in the past has routinely jailed its citizens on charges of contact with the country it calls the "Great Satan," Ahmadinejad's May 8 letter was implicitly endorsed by Iran's supreme leader, Ayatollah Ali Khamenei, and lavished with praise by perhaps the most conservative ayatollah in the theocratic government.

"You know, two months ago nobody would believe that Mr. Khamenei and Mr. Ahmadinejad together would be trying to get George W. Bush to begin negotiations," said Saeed Laylaz, a former government official and prominent analyst in Tehran. "This is a sign of changing strategy. They realize the situation is dangerous and they should not waste time, that they should reach out."

Laylaz and several diplomats said senior Iranian officials have asked a multitude of intermediaries to pass word to Washington making clear their appetite for direct talks. He said Ali Larijani, chairman of Iran's Supreme National Security Council, passed that message to the head of the International Atomic Energy Agency, Mohamed ElBaradei, who arrived in Washington Tuesday for talks with Secretary of State Condoleezza Rice and national security adviser Stephen J. Hadley.

Iranian officials made similar requests through Indonesia, Kuwait and U.N. Secretary General Kofi Annan, Laylaz said. American intelligence analysts also say Larijani's urgent requests for meetings with senior officials in France and Germany appear to be part of a bid for dialogue with Washington.

"They've been desperate to do it," said a European diplomat in Tehran.

U.S. intelligence analysts have assessed the letter as a major overture, an appraisal shared by analysts and foreign diplomats resident in Iran. Bush administration officials, however, have dismissed the proposed opening as a tactical move.

The administration repeatedly has rejected talks, saying Iran must negotiate with the three European powers that have led nuclear diplomacy since the Iranian nuclear program became public in 2002. Within hours of receiving Ahmadinejad's letter, Rice dismissed it as containing nothing new.

But U.S. officials who spoke on condition of anonymity said government experts have exerted mounting pressure on the Bush administration to reply to the letter, seconding public urgings from commentators and former officials. "The content was wacky and, from an American point of view, offensive. But why should we cede the high moral ground, and why shouldn't we at least respond to the Iranian people?" said an official who has been pushing for a public response.

Analysts, including American specialists on Iran, emphasized that the contents of the letter are less significant than its return address. No other Iranian president had attempted direct contact with his U.S. counterpart since the countries broke off diplomatic relations after student militants overran the U.S. Embassy in Tehran in 1979, holding 52 Americans hostage for 444 days.

Iranian analysts said Ahmadinejad's familiar list of grievances on Iraq, Israel and terrorism was designed largely for domestic consumption. CIA analysts and experts on Iran within the government said it also could be interpreted as an attempt to articulate points for possible discussion with Washington.

"There is no question in my mind that there has been for some time a desire on the part of the senior Iranian leadership to engage in a dialogue with the United States," said Paul Pillar, who was the senior Middle East intelligence analyst with the CIA until last fall.

"Much stranger first steps have led to dialogues than this letter. And as weird as the letter may be, if the Iranians want to begin discussions based on the theme of righteousness, that's something we should not be afraid to engage on," Pillar said. "We have pretty strong arguments about justice and righteousness of our own, so we should not shy away from that."*

Inside Iran, the letter effectively widened an opening toward the United States that began in March, with Larijani's unusually public acceptance of an American invitation to direct talks on the situation in neighboring Iraq. That acceptance provoked sharp criticism from hard-liners until it was publicly endorsed by Khamenei.

By contrast, Ahmadinejad's letter sparked lavish praise from perhaps the most conservative cleric in Iran's government, Ayatollah Ahmad Jannati, who chairs the Guardian Council, which oversees Iran's electoral process. Delivering the Friday sermon on May 12 in Tehran, Jannati called it "an extraordinary letter" and "an inspiration by God."

"The taboo is gone, for the first time when someone like Jannati endorses the message," said an Iranian political analyst who said he could not to be quoted by name because his employer had not authorized him to speak publicly.

Earlier attempts at outreach to Washington have been thwarted by conservatives. "The tradition is the hard-liners need American hostility," the analyst said. The most serious attempt was by Ahmadinejad's predecessor, reformist cleric Mohammad Khatami.

"When Khatami tried to do it, the leader rejected it," said the European diplomat. "But I guess they're worried enough. People don't want sanctions. Domestically, it's a good move."

Indeed, by last week, a prominent member of Iran's conservative parliament made headlines proposing talks with members of Congress.

"The taboo of the discussion is gone, but I don't think they've formed a consensus about normalization of relations," said a Western diplomat in Tehran. "But 'let's talk to the Americans' -- that was very controversial until recently."

The change appears rooted at least partly in Iran's political scene, now dominated entirely by conservatives. Pillar pointed out that with reformists driven from government, conservatives no longer fear that political credit for renewing contact with Washington will accrue to a rival domestic force. The Iranian public strongly favors restoring ties.

Laylaz also saw a second reason: Iran's nuclear program, which recently crossed a key threshold by enriching uranium.

"Now we have something to negotiate," Laylaz said. "The nuclear program of the regime has been successful, because five years ago nobody wanted to hear our voice."

Ordinary Iranians appear to approve of Ahmadinejad's overture. His letter remains at the top of the presidential Web site, http://www.president.ir .

"We have not had any relations for so many years, and Iran was always accused of being unwilling to talk," Masood Mohammadi, 23, said as he left Friday prayers last week. "Now Iran has taken the first step, and I hope the U.S. president replies in kind."

*I think the CIA has moved to Europe. It doesn't occupy the dangerous world the US does. It occupies the "let's all hold hands and sing Kumbaya" world of the Europeans. If anyone should recognize that Iran is aping the behavior of their coaches the North Koreans, it ought to be a senior analyst with the CIA. Instead, we get this "desire to engage in a dialog with the US" stuff. They don't want to discuss. They want to make an obeisance to the international community's fetish for discussions until it's too late to do anything about the urgent situation that provoked the discussions. If they want to discuss anything with us, it's when are we going to abandon our nuclear program lest they cut our oil off.